Primula boveana is a small plant, restricted to the environs of Mount Sinai (Egypt). It was named in honour of Nicolas Bové (1812-1841), one of the first botanists to study the flora of the Sinai Peninsula. The type was collected near Mt. St. Catherine by N. Bové in 1832.

It belongs to the subgenus Sphondylia (Duby) Rupr., which, together with its sister-group Dionysia Fenzl (previously regarded as a separate genus), forms a well-supported clade within Primula (Mast et al. 2001, Mast et al. 2006). All the species included in Sphondylia, as well as some Dionysia, are rare, narrow endemics distributed in wet refugia in arid areas from northeastern Africa to southwest Asia.

Richards and Eveleigh (2012) consider that Primula involucrata Sweet, 1839 is the valid name for this taxon; this is a catalogue name in Curtis’ Botanical Magazine referring to a figure and description of a plant called P. verticillata, but is actually from Egypt and is therefore clearly P. boveana.

Justification:Primula boveana qualifies as Critically Endangered because it is endemic to a tiny area (with an EOO of 13 km2 and AOO of less than 6 km2) of the high mountain area of the St. Katherine Protectorate in southern Sinai, Egypt. The total population size of mature individuals is less than 200, distributed among nine subpopulations. As the main threats are drought and climate change, effectively there is only one location. There is a continuing decline in habitat quality for this species, with evidence of declines in subpopulation numbers and numbers of mature individuals. Climate change is projected to further reduce the available habitat of this high-elevation specialist. Monitoring data suggests that the species might undergo extreme fluctuations but further observations are needed to determine this fact. Due to the small number of mature individuals and the population structure this species would also qualify as Endangered under Criterion C2a(i) and D

Primula boveana has been reported as one of the rarest plant species worldwide (Richards 2003, Jimenez et al. 2014). It is endemic to the high mountain area of the St. Katherine Protectorate (SKP) in southern Sinai, Egypt, with a narrow altitudinal range between 1,745 and 2,210 m asl. The gorges of Shaq Mousa and Shaq El Garagniah are the most important places for this species within the area of SKP. Its extent of occurrence (EOO) is c. 13 km2. The subpopulations are small in size and on average each cover 5 m2 of land, with the actual area occupied by the species being c. 0.7 km2. The area of occupancy (AOO), based on a 2x2 km grid over these subpopulations, is6 km2.

Most of the Primula boveana subpopulations are small, with individual plants occurring sporadically in space in little groups where the soil is wet. The number of mature plants has declined from ‘abundant’ in 1832 (Richards 2003), almost 2,000 in 1991 (Al Wadi 1993), and 336 in 2007 (Jimenez et al. 2014). In 2014, the total global population size was recorded at c. 1,010 individuals during the last survey carried out by SKP rangers, but only 165 individuals were mature (about 16% of the total population). There are nine very small but clearly separate subpopulations, but only seven of them contain between three and 65 mature individuals. During the last 10 years these subpopulations have shown large changes in the total number of individuals, cover and density. There was a peak observed between 2008 to 2010 (345 to 360 mature individuals) but now (2012-2014) the population is at its lowest observed number; it may be that the species undergoes extreme fluctuations. In 1991, the species was distributed in more than 12 subpopulations including Gabal St. Katherine and Elgalt Elazrak which have not been recorded recently. These subpopulations disappeared in the period between 2001 and 2007. The Elgalt Elazrak subpopulation appeared again from 2007 to 2012, before disappearing again. Areas including Shaq Elgragenia that were recently recorded as one of the main sites for P. boveana were not found in the past (2005 to 2008). The Kahf Elghola subpopulation was the main site for P. boveana in the past with 30 mature individuals recorded there in 2009 (Omar et al. 2012) but no mature individuals were found there in 2014, only four immature seedlings. The distribution and size of this species is dependent on the presence of water (rainfall) and this has resulted in the species undergoing fluctuations in the past, at present and likely in the future due to irregular precipitation. These fluctuations in the subpopulations lead to fluctuations in both EOO and AOO. Drought is the main limiting factor for this species, and because the plant is distributed within such a very small restricted area, the effect of this threat will be felt by the entire population; thus they are all effectively in one location.

Primula boveana is a perennial with stems up to 60 cm long. The greyish-green leaves are spear-shaped, up to 20 cm long in a rosette. It bears several whorls of long-tubed, golden-yellow, scented flowers in late spring, and reproduction is by seed in late summer. It is restricted to montane wadis fed by melted snow and distributed in moist ground in the vicinity of wells and sheltered mountain areas, especially cliffs and caves with steep slopes of up to 90º on northeast- (78%) and east-facing (22%) granite. The cold winter climate (minimum temperature can reach -10ºC) and cool summers (maximum about 29ºC) of the high elevations of Mt. St. Katherine are the coolest on the peninsula (Omar et al. 2013). The arid climate has a mean annual rainfall of about 37.5 mm (between 1971-2014), some in the form of snow, but there is great inter-annual variation with up to 300 mm in any one year, usually between October and May. Relative humidity is low, ranging from 10-35% (data for 2005-2014), and potential evaporation rates are very high, in excess of 20 mm/day during August. Primula boveana grows in loamy sandy soil with average pH 8.2, electrical conductivity 760 µs/cm and organic matter 3.5% (Omar 2013a). Due to its restricted micro-habitat, P. boveana is the dominant species in most sites, but its associated species are Adiantum capillus-veneris L., Mentha longifolia (L.) Huds., Hypericum sinaicum Boiss. and Juncus rigidus Desf. (Omar 2013a).

As a result of climate change, the wild population of this species could be in extreme danger in the relatively near future. The most important natural threats are the long-lasting droughts, the very scarce irregular precipitation during the year, the fragmentation inherent to its habitat, and the possibility that rare floods may cause harm such as uprooting (5% loss observed). Apart from climate change, the most important human impacts are reductions in water availability caused by collection for human consumption from the nearby areas, possible sheep and goat grazing, insect pests that eat the vegetative parts and may cause reductions in plant vigour (observed), and a species of ant that collects the seeds, perhaps causing reductions in the reproductive rate.

The subpopulations have very low genetic variation amongst individuals within them, and gene flow between them must be extremely low or actually zero. Conversely, genetic differentiation among the subpopulations is high (Jimenez et al. 2014). It may self-fertilize most of the time, apparently with little or no detrimental effects (Al Wadi and Richards 1993, Jimenez et al. 2014). Probably deleterious alleles have been purged a long time ago, possibly making inbreeding depression not a major problem today, although also possibly restricting its ability to evolve in response to environmental change (Jimenez et al. 2014).

About four million people from 51 nationalities visited SKP from 2003 to 2014 with an average of 335,000 people per year. Most of these visitors focused on the northern part of SKP, which is a world heritage site. Many of the tourists go on safaris and camp in remote areas; usually safaris extend for many days using different camping sites with the main camp sites at Sad Abu Hebik, Shaq Mousa, Gabal Mousa, Wadi Tenia, and Wadi Gebal. Five of the nine subpopulations recorded have minor influences from tourism. Some of the negative impacts associated with tourism include collection of plants as souvenirs from the SKP. Soil compaction due to trespassing, climbing and trampling leads to poor vegetation cover. Garbage also may lead to deterioration in species growth.

Additionally because of its importance and rarity, this species is a target for collection. However, the species is not commercially or traditionally used in Sinai, but it has been collected for pharmacological testing by various scientific research centres. The unmanaged collecting for this species will lead to deterioration in population size.

Water is being relocated in some localities from elevated wadis which are rich in water to supply to low wadis. This activity leads to consumption of water from wells and results in habitat deterioration and declines in population size.

The entire global distribution of Primula boveana is inside the St. Katherine Protectorate. Six from the nine subpopulations are already protected by fenced enclosures, and regular monitoring by SKP rangers takes place every two years to detect the effects of this protection on population trends. On average 48 checks are made every year to keep a watch on the current situation for the plant and its habitat, and to record any detrimental activities. Funded by UNEP, the Medicinal Plants Conservation Project tried to conserve some important species, P. boveana among them, using cultivation inside greenhouses as well as storing its seeds for future use. Studies were initiated of its ecological, morphological and reproductive ecology, and the threats to its existence (Omar 2013b). Much more is needed, however.